Hepatitis B

Organism

Hepatitis B is an infectious disease caused by the hepatitis B virus (HBV) that primarily affects the liver. HBV is mainly spread through direct contact with infected blood and blood products but can be sexually transmitted. 

Clinical presentation
Acute hepatitis B virus (HBV) infection may be asymptomatic or may present with the following symptoms: 
  • lethargy, 
  • nausea, 
  • fever, 
  • anorexia for a few days then jaundice, 
  • pale stools and dark urine. 

The incubation period is 45-180 days (mean: 60 days)

In some cases of HBV infection, the virus will not be eliminated and the person will become chronically infected (i.e.HBsAg or HBV DNA (PCR) has been detected on two occasions at least 6 months apart). Chronic HBV infection is commonly asymptomatic. However, there is no such thing as a healthy carrier. Even if they appear to be healthy, people with chronic HBV should be monitored regularly (every 6-12 months) by their GP for signs and symptoms of liver disease

Chronic HBV (CHB) infection is usually asymptomatic until the patient has progressed to cirrhosis (liver damage and scarring). Symptoms of cirrhosis include:

  • jaundice
  • ankle swelling,
  • ascites,
  • GI bleeding,
  • Encephalopathy

There are four phases of CHB:

  • Immune tolerance
  • Immune clearance
  • Immune control
  • Immune escape
The patient’s immune response in each phase determines the outcome of infection and the severity of cirrhosis which is caused by the immune response rather than the hepatitis B virus (HBV) itself. Progression to cirrhosis is most likely during the immune clearance and immune escape phases; treatment should be considered for patients in these phases, see Treatment

People with cirrhosis due to chronic HBV are at increased risk of developing hepatocellular carcinoma.

People with chronic HBV may transmit infection vertically (from mother to baby), or through sexual or percutaneous exposure.

STI Atlas (external site)

Investigations

Laboratory investigations of HBV infection include:

  • tests to diagnose HBV infection
  • tests for pre-treatment assessment of people with chronic hepatitis B infection. See Follow up.
  • follow up tests to monitor liver function +/- response to treatment. See Follow up

Tests for diagnosing HBV infection

Patients of unknown HBV status should always have three initial tests performed (HBsAg, Anti-HBs and Anti-HBc) to determine infection status and the need for

vaccination. Specify the above tests on the request form rather than ‘hepatitis B serology’ 

Those at high-risk of HBV who should be offered testing include:

  • people who inject drugs
  • men who have sex with men
  • people with multiple sexual partners, including sex workers
  • people diagnosed with any STI, test for hepatitis B when testing for STIs and at the 3 month follow-up appointment
  • partners and household contacts of people with acute or chronic hepatitis B
  • people born in intermediate and high prevalence countries
  • Aboriginal and Torres Strait Islander peoples.

HBsAg testing is recommended for all pregnant women in the first trimester of each pregnancy to allow appropriate measures to be implemented to prevent newborn infants developing chronic HBV infection.

Window Period

The tests detects antibodies to and antigen of the virus. There is a period after infection, when the test will not detect antibody or antigen because they are yet to be produced or are present at a level that cannot be detected. This is called the window period which may last up to 3 months.

Interpreting serology

HBsAg
anti-HBc
anti-HBs 
positive
positive
positive 
Chronic HBV infection
HBsAg
anti-HBc              
IgM anti-HBc*
anti-HBs
positive
positive
positive
negative
 Acute HBV infection
*(high titre)
HBsAg
anti-HBc
anti-HBs
negative
negative
negative
 Susceptible to infection (vaccination
should be recommended)
HBsAg
anti-HBc
anti-HBs
negative
negative
positive
Immune due to Hepatitis B vaccination
HBsAg
anti-HBc
anti-HBs
negative
positive
negative
Various possibilities including: distant
resolved infection, recovering from acute HBV, false positive,
 ‘occult’ HBV

Source: Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine - Decision making in hepatitis B (external site)

See Follow up section below for details of further investigations required prior to referral of patients with chronic HBV infection. 

Treatment

Treatment of chronic hepatitis B (external site) can significantly reduce progressive liver damage and loss of liver function. It will generally consist of oral antiviral therapy which needs to be taken on a long-term basis. Less commonly, pegylated interferon may be used 

GPs can be be authorised to prescribe hepatitis B medicines. 

Patients with chronic HBV should be offered hepatitis A vaccination unless they are known to be already immune because the case fatality rate is high if they develop hepatitis A infection. 

See Follow up section below for details of further investigations required prior to referral of patients with chronic HBV infection.

Education, counselling and prevention

Informing your patient

  • Provide contact details of support services and relevant material.
  • Use a professional interpreter if required. Call Translating and Interpreting Service (TIS) 13 14 50.
  • Fact sheets for patients (Healthy WA)

Reduce transmission

Alcohol - a modifiable risk factor for disease progression

 Status Advise
Early disease with no risk factors for progression, 
consistently normal ALT and normal clinical
examination
Alcohol advice as per general population, NHMRC 
Australian guidelines to reduce health risks from 
drinking alcohol (external site)
Significant fibrosis At most one standard drink/day and no binging
Cirrhosis Aim for total abstinence 

Refer to alcohol and drug services as necessary 

Psychological support and counselling 

For parents and their family/partners, telephone support, education and support groups are available through Hepatitis WA (external site)

Vaccination

The National Health and Medical Research Council's (NHMRC) Immunisation Handbook (external site) recommends that the following groups are among those who should receive hepatitis B vaccine:

  • household or other close (household like) contacts of people with hepatitis B
  • sexual contacts of people with hepatitis B
  • men who have sex with men
  • people who inject drugs
  • sex industry workers
  • individuals with chronic liver disease and/or hepatitis C
  • haemodialysis patients
  • HIV positive people and other immunocompromised people
  • inmates of correctional facilities 
  • people at occupational risk e.g. healthcare workers, ambulance personnel, dentists, police, staff of correctional facilities, embalmers, tattooists and body-piercers
  • migrants from hepatitis B endemic countries
  • Aboriginal and Torres Strait Islander people.

Serological testing for evidence of past (or current) hepatitis B infection prior to vaccination may be warranted for certain older children, adolescents and adults, especially those at increased risk of acquiring hepatitis B infection, e.g. people who inject drugs, sex industry workers, immunocompromised people, and those living in communities with higher prevalence of HBV, including migrant communities and Aboriginal and Torres Strait Islander people. Serological testing allows people with HBV infection to be identified which facilitates clinical and public health management to prevent liver damage and onward transmission, respectively

Standard regimes for vaccination include:

  • 0, 1 and 6 months
  • 0, 1, 2 and 12 months
  • 0, 7, 21 days and 12 months for rapid vaccination of those at highest risk.

Vaccination should be administered into the deltoid muscle.

If doses are missed the course does not need to be restarted, but all doses should be completed. 

Serological testing following hepatitis B vaccination

Post-vaccination testing for Anti-HBs antibody and HBsAg levels is recommended:

  • 3 to 12 months after completing the primary vaccine course in infants born to mothers with chronic hepatitis B infection.
  • 4 to 8 weeks after completion of the primary course for
    • those at significant occupational risk (e.g. healthcare workers whose work involves frequent exposure to human tissue, blood or body fluids)
    • those at risk of severe or complicated HBV disease (e.g. persons who are immunocompromised, and persons with pre-existing liver disease not related to hepatitis B)
    • sexual partners and household, or other close household-like, contacts of persons who are infected with hepatitis B
    • those in whom a poor response to hepatitis B vaccination may occur (e.g. haemodialysis patients, persons with bleeding disorders vaccinated via the SC route).

Post-vaccination serology is NOT recommended for other groups 

A single booster dose (4th dose) of vaccine can be given to confirm non-responder status. Those who are still non-responders after being given the booster/4th dose should have 2 further doses of hepatitis B vaccine at monthly intervals, and be re-tested for anti-HBs levels at least 4 weeks after the last dose.

Management of partners

On receipt of a notification of a hepatitis B case, the local public health nurse follows up with the reporting doctor and with the case to discuss household and sexual contacts. All household and sexual contacts of a person with chronic hepatitis B should be tested for hepatitis B infection. Non-immune household and sexual contacts should be offered free hepatitis B immunisation (and hepatitis B immunoglobulin if significant exposure has occurred). 

For more information see:

Follow up

Chronic hepatitis B 

HBsAg or HBV DNA (PCR) has been detected on two occasions at least 6 months apart

Assessment

Review your patient for evidence of decompensated liver disease - one or more of the clinical complications of chronic liver disease:

  • peripheral oedema
  • low albumin
  • high INR
  • variceal bleeding
  • ascites
  • encephalopathy.
High risk of progression:
  • male
  • >45yrs of age
  • heavy alcohol intake
  • family history of hepatocellular carcinoma (HCC)
  • co-infection with HIV/HCV/HDV
  • presence of cirrhosis
  • long duration of infection.

Management 

Initial Investigations (tests in bold are required prior to referral)

  • FBC
  • U&E
  • INR
  • Iron studies
  • LFTs (AST, ALT, ALP, GGT, Albumin, Bilirubin)
  • HBeAg/HBeAb
  • HBV DNA (quantitative viral load)   
  • Alpha-fetoprotein(AFP)
  • Liver/abdominal ultrasound
  • HCV serology
  • HAV serology
  • HIV serology
  • HDV serology
  • ANA/ASMA

Ongoing

Review every 6-12 months and monitor for signs and symptoms of liver disease e.g. signs: palmar erythema, spider naevi, jaundice, ascites, encephalopathy, hepato-splenomegaly.

Investigations (should be guided by HBeAg and LFT): 

 Previous result  Investigation and frequency
 HBeAg LFT LFT (ALT) HBV DNA  HBeAg and HBeAb
 +ve ALT<2xULN
 6-12 monthly  12 monthly  6-12 monthly
 +ve
ALT>2xULN
 3-6 monthly  3-6 monthly 3-6 monthly
 -ve normal
 6-12 monthly  12 monthly -
 -ve abnormal  3-6 monthly  3-6 monthly -

ULN = upper limit of normal level

Screening for hepatocellular carcinoma

Ultrasound and AFP every 6 months for those at high risk:

  • presence of cirrhosis
  • family history of HCC
  • Aboriginal and Torres Strait Islander people >50yrs
  • Asian men >40yrs
  • Asian women >50yrs
  • African people >20yrs
  •  >40yrs with raised ALT +/- high HBV DNA (>2,000 IU/ml).

Symptom Management 

  • Control of fatigue: advise planning rest periods during the day and the addition of light to moderate exercise into their routines to reduce fatigue.
  • Psychological support and counselling available through Hepatitis WA (external site)

Referral

Urgent (seen <1 week): If evidence of decompensated liver disease discuss directly with Gastroenterology/General Physician at your local hospital and fax a completed referral directly to the relevant hospital.

Routine

Refer those with:

  • cirrhosis
  • pregnancy
  • raised AFP
  • HBsAg +ve and HBeAg +ve with ALT >2x ULN
  • HBsAg +ve and HBeAg –ve with HBV DNA >2000 IU/ml and raised LFT
  • HBsAg +ve and >40yrs of age with ALT 1-2x ULN
  • High risk of progression and/or are complex.

Information to include with referral:

  • likely date and mode of transmission
  • alcohol consumption
  • other drugs (include injecting drug use)
  • current medications
  • symptoms and signs of hepatitis (e.g. jaundice)
  • investigation results (those in bold in management section).

Note: Patients with HIV co-infection and who are asymptomatic with no signs of chronic liver disease can be managed by Infectious Diseases/Immunology

Public health issues
  • Notify WA Health of any cases of HBV
  • Contact tracing, testing and vaccination of non-immune sexual, family and household contacts are important to prevent further transmission of HBV. 

Post-exposure prophylaxis 

Percutaneous, ocular or mucous membrane contacts should be given hepatitis B immunoglobulin (HBIG) 400 IU intramuscularly (100IU, if body weight <30kg), as a single dose within 72 hours of exposure.

Individuals sexually exposed should be given HBIG within two weeks of sexual contact. Adults should be given HBIG 400 IU intramuscularly, as a single dose, and vaccination commenced within 7 days of exposure. Hepatitis B vaccination and immunoglobulin can be given at the same time, but at different sites.

Notifications

This is a notifiable infection. Medical practitioners must complete the appropriate notification forms for all patients diagnosed with a notifiable STI/HIV, as soon as possible after confirmed diagnosis.